Telephone system



G. T. BAKER TELEPHONE SYSTEM Filed Aug. 30, 195" Aug. 13, 15949.

ATT)? INVENTOR Patented Aug. 13, 1940 PATENT OFFICE TELEPHONE SYSTEMGeorge Thomas Baker, Liverpool, England, as-

signor to Associated Telephone & Telegraph Company, Chicago, Ill., acorporation of Delaware Application August 30,

In Great Britain r 8 Claims. The present invention relates to telephonesystems and is more particularly concerned with the, provision of zonemetering facilities in systems not employing register-controllers. Fromcate the multi-iee motoring equipment in a common group and to associatea set of equipment with an outgoing junction relay set, for example,when desired. Hitherto, however, this arrangement in a simple form hasnot been possible owing to lack of time in an interdigital pause toensure the performance of both the normal switch hunting operation for afree junction relay set and in addition the extra hunting operationrequired for an idle multi-metering equipment. The chief object of theinvention is to overcome this difficulty by the use of a so-calledmechanical impulse repeater by which is meant a registering. and sendingdevice in which the length of a train of outgoing impulses is determinedby a mechanical marking corresponding to the received train rather thanby an electrical marking as is more-usual.

According to one feature of the invention in a telephone system arrangedfor zone metering an outgoing trunk has associated with it a mechanicalimpulse repeater arranged to store incoming impulses and re-transmitthem only after a set of common auxiliary equipment has been asso ciatedwith the trunk.

According to another feature of the invention in a telephone systememploying mechanical impulse repeaters for impulse repetition overjunction lines the transmitting operation of a mechanical impulserepeater is arranged to be delayed until the association'with thejunction of a set of common metering control equipment, to whichtheimpulses are also repeated. o i

A further feature of the invention is that in a telephone systememploying mechanical impulse repeaters for impulse repetition overjunction lines a mechanical impulse repeater is provided with two setsof springs for retransmitting incoming impulses one set serving forrepeating D impulses over the junction line while the other serves foroperating auxiliary equipment.

The invention willbe better understood from the following description ofone method of carrying it into effect, reference being had to theaccompanying drawing which shows the circuit elements of a junctionrelay set JRS adapted to incorporate a mechanical impulse repeaterarranged to operate in accordance with the invention. On the seizure ofthe junction relay, set a start. signal is extended to-the allotter Awhich an economic standpoint it is preferable to lo- 1937, Serial No.161,580 September 10, 1936 selects an idle multi-metering equipment MMEwhereupon a rotary switch associated with this equipment hunts for thecalling relay set. The circuit diagram has only been shown in sufficientdetail to enable the principle underlying the in vention to beunderstood. I

It is assumed that use is being made of a mechanioal impulse repeater orregenerator of the type disclosed in the J. W. McClew and C. R. WoodlandPatent 2,188,461, issued January 30', 1940, which in addition to storageand subsequent transmission of the digits in corrected form alsoprovides a controlled delay between successive digits transmitted inorder to adequately cover the hunting time of the switches in the train.It will be understood however that the invention is not limited to adevice of this precise construction. I

Referring now to the drawing, itxwill be seen that on seizure of thejunction relay set the'sub scribers loop extended over the precedingselector or selectors operates relay A which in turn energises theslow-to-release relay B. Relay B thereupon applies earth to the commonstart lead S extending to the allotter A and thus 0p erates relay STwhile at the same time an impulsing circuit is prepared for theregenerator receiving magnet RM. Relay ST completes a self-interrupteddriving circuit for the allotter magnet AM by way of the interruptercontacts am whereupon the switch rotates in search of an idlemulti-metering equipment which is marked by battery potential on the A2bank. When a free outlet is reached relay G operates to out the driveand at the same time due to its low'resistance immediately guards theoutlet seized. Relay G extends earth over the Al wiper and bank toself-drive the junction relay set finder magnet JFlVLv It will beappreciated that the allotter may be adapted in a well-known mannertopreselect an idle metering equipment in the intervals between callsbut under heavy traffic conditions there would be insufficient time forpreselection and the operation would be as described above. Immediatelythe finder switch JF reaches the calling junction relay set which is'marked by battery potential on the JFZ bank, relay SW operates to cutthe drive and provides an immediate guard on the outlet seized. At thesame time relay JF is operated and a circuit is prepared for themeter-fee switch magnet MFM.

Meanwhile onreception of dialled impulses, relay A responds and repeatsthem to'the regenerator receiving; magnet RM which mechanically storesthe digits in a manner described in the specification previouslyreferred to.

On operation of relay JF which signifies that an idle metering equipmentis available, a circuit is completed to operate relay BY by way of theregenerator off-normal springs N, closed upon seizure of the mechanicalimpulse repeater, whereupon this relay connects one set of regeneratorimpulse springs IMF! to the outgoing junction and starts up the sendingout of the digits stored in the regenerator. As each regenerated digitis transmitted over the junction the impulse springs IMPZ transmitsimilar impulses to operate the multi-fee switch magnet MFM acorresponding number of times. The multi-fee switch is adapted toexercise control in accordance with the digits transmitted, forinstance, as described in the R. Taylor and G. T. Baker application Ser.No. 134,500, filed April 2, 1937, whereupon after reception of theappropriate number of digits a signal is sent back to cause the requiredmeter pulse lead to be connected up in the junction relay set. Thecommon equipment is then disassociated from the junction relay set andis available for further common use.

It will be appreciated that if a multi-metering equipment associatesitself with a junction relay set before storage of all the dialleddigits as would generally be the case, trains of impulses may bereceived and transmitted simultaneously by the regenerator.

In case the junction is worked on a bothway basis, on calls incomingover the junction the metering equipment would not be taken into use.

It may be pointed out that even if satisfactory impulse repeatingconditions can readily be obtained the use of impulse regenerators canbe justified on an economic basis in View of the simplification andsaving in respect of the multimetering equipment. If however the impulserepeating conditions are such as to require the use of impulseregenerators or the like in any event, the saving represented by thearrangement according to the invention is correspondingly greater.

I claim: I

1. In a repeater, a relay group, a mechanical impulse storage andretransmitting device, a trunk line over which impulses are transmittedto said device, means in said relay group operated responsive to saidimpulses for controlling said mechanical device to store a plurality ofsaid impulses, an outgoing trunk line, a set of impulsing contactscontrolled by said mechanical device, and means for simultaneouslyconnecting said impulsing contacts to said outgoing trunk line and forstarting said mechanical device to operate said contacts after aplurality of impulses have been stored to retransmit all of the storedimpulses over said outgoing trunk line.

2. In a telephone system, a mechanical impulse repeater arranged tostore and retransmit impulses, an outgoing trunk line associated withsaid repeater, an incoming trunk line, common metering controlequipment, means for controlling said repeater to store impulsesreceived over said incoming trunk line, means for automaticallycontrolling said common equipment to find and connect with saidrepeater, and means in said repeater operated responsive to saidconnection for controlling said repeater to start retransmitting saidstored impulses over said outgoing trunk line and to said commonequipment simultaneously.

3. In a telephone system, a plurality of mechanical impulse repeaters, alike plurality of associated trunk lines, common auxiliary equipment,means in said repeaters for storing impulses received over the incomingend of associated trunk lines, means in said repeaters forretransmitting the stored impulses over the outgoing end of said trunklines, means controlled by an operated repeater for associating saidcommon equipment therewith, and means in the operated repeater fordelaying the retransmission of stored impulses until said commonequipment is associated therewith, and means in the operated repeateroperated responsive to association therewith of said common equipmentfor retransmitting said stored impulses to said common equipment andover the associated outgoing trunk line.

4. In a telephone system, a trunk line, a mechanical impulse repeaterassociated with said line, means in said repeater operated responsive toimpulses received over the incoming end of said trunk line for storingsaid impulses, auxiliary equipment, means controlled responsive to theoperation of said repeater for associating said auxiliary equipment withsaid repeater, means in said repeater operated responsive to the saidassociation for starting the retransmission of stored impulses, two setsof springs for retransmitting the stored impulses, one of said settransmitting impulses over the outgoing end of said trunk line and theother of said sets transmitting impulses to said auxiliary equipment.

5. In a telephone system, a relay group, an outgoing trunk lineassociated with said relay group,

a combined register and impulse transmitterv associated with said relaygroup, an allotter, multi-metering equipment, a trunk line over whichsaid relay group is seized and over which a plurality of series ofimpulses are transmitted to said relay group, means in said relay groupoperated responsive to said seizure for starting said allotter andoperated responsive to said series of impulses for controlling saidregister in accordance with the impulses transmitted, means in saidallotter for finding and seizing said multimetering equipment, means insaid metering equipment operated responsive to the seizure thereof forfinding and connecting with said relay group, and means in said relaygroup operated responsive to said last connection for controlling saidcombined register and transmitter to simultaneously retransmit series ofimpulses corresponding tothe series of impulses received to saidmetering equipment and over said outgoing trunk line.

6. In an automatic telephone system, a trunk relay group for use incompleting a connection between a calling and a called subscriber, zonemetering apparatus for controlling the operation of a callingsubscribers meter, switching apparatus for operatively associating saidzone metering apparatus with said relay group, and means in said relaygroup for storing digit impulses and for retransmitting impulses inaccordance with the digits stored to set automatic switches to completethe connection to the desired called subscriber and to set the zonemetering apparatus accordingly in order that the calling subscribersmeter may be controlled thereby.

7. In an automatic telephone system, a trunk line, a trunk relay groupassociated with said line, a mechanical impulse storing andretransmitting device associated with said relay group, zone meteringapparatus, an allotter for associating said metering apparatus with saidrelay group, means responsive to the extension of a call over said trunkline to said relay group for starting said allotter to cause theconnection of said metering apparatus with said relay group, means insaid relay group for operating said mechanical device to store impulsesreceived over said trunk line, means for delaying the retr'ansmission ofsaid impulses until said metering apparatus is associated with saidrelay group, said last means operated responsive to connecting of zonemetering apparatus to said relay group to control said mechanical deviceto retransmit the stored impulses over the outgoing end of said trunkline to complete a connection and to simultaneously transmit saidimpulses to said zone metering apparatus so that the calling subscribermay be properly charged for the connection according to the zone andduration of the call.

pulses over said outgoing trunk line operated re- 1 sponsive to saidfinder switch finding said relay group,

GEORGE THOMAS BAKER.

